1. Technical Field
The present invention relates to anti-theft devices which attach to commodities for preventing theft of the commodity. In particular, it relates to a method and apparatus for using an audible anti-theft tag with multiple audio levels to alert merchants to removal of goods, which uses a unique power system to extend the operational life of the audible alarm, and which uses a unique shunt-proof multi-lead lanyard to detect when the lanyard is severed.
2. Background
Theft of all kinds has been an ongoing problem for virtually all retail establishments. One kind of theft, shoplifting, has caused substantial losses for retailers due to its widespread use. In an attempt to address this problem, a variety of devices have been developed to limit shoplifting losses by automatically alerting the retailer when an item of merchandise is being illegally removed from the premises.
One type of anti-theft device is the anti-theft tag (an “EAS” tag). An anti-theft tag is typically a small device which is secured to an inventory item with a securing pin. EAS tags are attached to goods prior to sale. When a customer purchases the goods, the salesman uses a detacher device to remove the EAS tag from the goods by disconnecting the securing pin from the EAS tag.
In the event a shoplifter attempts to leave the merchant's premises with goods, the goods will pass by detector devices at the store exit. When the detector senses a tag being removed from the store, it alerts the retailer via an alarm that is controlled by the detector.
Anti-theft tags of this type typically contain an EAS tag which holds a tuned circuit or antenna and associated circuitry, along with mechanical methods of securing the EAS tag to a securing means. The securing means would typically be a pin assembly that is a cap-like structure with a securing pin. The securing pin is pushed through an item, such as a garment, and then secured to the EAS tag. Once a customer has made a purchase, the employee would remove the anti-theft tag so that the customer can take the item out of the store without setting off an alarm. A problem associated with this type of anti-theft tag is that once the stolen goods with the anti-theft device are removed from the merchant's premises, the merchant may not be able to determine where the goods have gone. It would be desirable to structure an anti-theft tag such that stolen goods can be detected even after they are out of range of the anti-theft tag detectors.
Another problem associated with anti-theft tags is that it is possible to remove them prior to taking the goods past the detectors. It would be desirable to provide retailers with an anti-theft tag that will alert a merchant when the tag is removed from goods in an unauthorized manner without requiring the tag to be moved past the anti-theft tag detector at the store exit.
One attempt to address problems related to removal of tags and tracking goods after they have left the merchant's premises has been the development of anti-theft tags that have audible alarms. Unfortunately, these tags may also be limited in effectiveness due to the limited life span of internal batteries. Reductions in battery lifespan are caused by the power drain created by the audible alarm and by other internal circuitry. It would be desirable to have a method of improving the reliability of audible anti-theft tags by reducing battery drain, and thereby improving the effective useful life span of the internal batteries.
Another drawback to conventional audible anti-theft tags is that, due to the aforementioned battery problems, they may not be able to produce a sufficiently loud alarm when the anti-theft tag is detected passing an anti-theft detector, or when the EAS tag is forcibly removed from the pin assembly.
Yet another problem associated with conventional EAS tags is created by the need to use these tags in combination with large or irregular shaped items which cannot be secured via a securing pin. The use of a lanyard (i.e., a lead which extends in a loop from the EAS tag and around a package) allows large or irregular shaped packages to be secured to the EAS tag. In the prior art, the lanyards have sometimes been equipped with an internal electrical lead. The purpose of this lead is to provide a signal path that indicates to the EAS tag at the lanyard has not been severed. Unfortunately, thieves have discovered that by shunting the lead, the lanyard can be severed without alerting the EAS tag. It would be desirable to have a method of activating the EAS tag and/or its audible alarm even if a thief had shunted the lanyard.
While the prior art has provided numerous types of anti-theft tags, it has failed to provide an audible anti-theft tag that is difficult to defeat, which has multiple methods of activating the alarm by notifying merchants both when the anti-tag is removed or when the anti-theft tag is moved past an anti-theft tag detector, which has sufficient battery life to continue to produce an audible alarm for a substantial period of time, and which has an optional lanyard which will trigger the audible alarm and/or EAS tag even if the lanyard has been shunted.